Method and operation of a well jet device inkwell testing and development and the well jet device for carrying out said method

ABSTRACT

The invention relates to jet device used for extracting oil from wells. The inventive method consists in the following: a pump, a connecting and disconnecting unit, a valve unit, a packer and a shank are mounted on a tubing string before actuating the inventive device. A perforator is run into the well on a mounting seat in the pass channel of the pump, the packer being released. Differential pressure being produced, the perforator is blasted against the productive stratum which is then drained. The perforator being replaced by the transmitter and receiver-transducer of physical fields, the stratum is studied while the pump operates. Said transmitter and receiver-transducer being pulled from the well, a valve chamber and a blocking insert separating the cavity of the tubing string from environment are thrown into the well. The well starts to work in a natural flow regime. When the production rate decreases, the well is suspended, the blocking insert is substituted by a depression insert provided with a manometer and a debitometer and the well production is measured while fluids are pumped out. The flow rate-bottomhole pressure graph is plotted according to indications of instruments and interpreted, thereby defining the sizes of a pump. The required pump is run into the well along the tubing string and the well is put into operation by a power method. The invention is directed to improve reliability of the operation of said device.

FIELD OF THE INVENTION

This invention relates to the field of pumping engineering, mainly towell jet devices used for oil production.

PRIOR ART

Known in the art is a method of operation of a well jet unit, includinglowering in the well a tubing string with a jet pump, a packer and aperforator, arranging the said packer against a productive stratum andblasting the perforator, with the subsequently pumping a liquid workingmedium by the said jet pump (SU 1146416 A).

Known from the above source is a well jet unit comprising a jet pumparranged in the well on the piping string and a perforator arrangedbelow the said jet pump.

The said unit enables to perforate the well and to pump a variety ofproduced media out of the well while intensifying the medium production;however, a strictly defined arrangement of the perforator relative tothe jet pump does not enable, in a number of cases, the optimalpositions of the perforator and the jet pump relative to the productivestratum which lowers the efficiency of the work on draining the well.

The closest, as to the technical essence and the achieved result, to theinvention in the part of the method as the object of the invention isthe method of operation of a well jet unit, which includes installationof a jet pump with a through passage and a packer onto the pipingstring, lowering of that assembly into the well, release of the packerand creation of the required pressure drawdown in the area below thepacker by pumping the process fluid out of the area below the packer (RU2121610 C1).

Known from the same patent is a well jet unit comprising a packer withthe central passage and a jet pump with an active nozzle, the mixingchamber and the through passage having the mounting seat for installinga sealing assembly with the axial passage, all of them being installedonto the piping string, the said unit is provided with a transmitter andreceiver-transducer of physical fields, which is arranged in the areabelow the packer on the side of entry of the pumped-out medium into thejet pump and installed on the well-logging cable passed through theaxial passage of the sealing assembly, the output of the jet pump isconnected to the area around the piping string, the input of the passagefor supplying the pumped-out medium to the jet pump is connected to theinner cavity of the piping string below the sealing assembly, and theinput of the passage for supplying the liquid working medium to theactive nozzle is connected to the inner cavity of the piping stringabove the sealing assembly.

The said method of operation of the well jet unit and the unit forcarrying out the said method enable to perform various productionoperations in the well below the level at which the jet pump isinstalled, including those performed by reducing pressure differenceabove and below the sealing assembly. But, the known unit does notenable to exploit its potential in full due to non-optimal arrangementand dimension relations of various structural elements of the well jetunit.

DISCLOSURE OF INVENTION

The objective of this invention is to optimize the arrangement anddimensions of various components of the construction of the well jetunit and, owing to it, to raise the reliability of its operation.

The stated objective in the part of the method is achieved owing to thefact that in the method of operation of the well jet unit in testing anddeveloping wells, which includes installation of a jet pump with athrough passage and a packer onto the piping string, lowering of thatassembly into the well, release of the packer and creation of a requiredpressure drawdown in the area below the packer by pumping the processfluid out of the area below the packer with the jet pump, the pipingstring is additionally provided with: an assembly for disconnecting andconnecting the piping string, a valve assembly with the mounting seatfor installation of a check valve, a shank with an input cup, and arecirculation valve installed in the wall of the piping string above thejet pump; first the piping string is assembled by successivelyinstalling, top-down on the piping string, a jet pump, an assembly fordisconnecting and connecting of the piping string, a valve assembly withthe mounting seat for installing a check valve, a packer and a shankwith an input cup; when lowering the assembly the packer is installed atleast 50 meters above the roof of the productive stratum and the inputcup is installed no more than 2 meters above the roof of that stratum;after releasing the packer a perforator on a well-logging cable islowered into the well together with a sealing assembly installedthereon, which is seated onto the mounting seat in the through passageof the jet pump, the said perforator being arranged against theproductive stratum; further a required pressure drawdown onto thestratum is created with the use of the jet pump, the perforator isblasted, and the stratum is drained until the process fluid under thepacker is completely replaced by the stratum fluid; then the perforatortogether with the sealing assembly are lifted to the surface, atransmitter and receiver-transducer of physical fields with the sealingassembly are lowered into the well on the well-logging cable, and, whileoperating the jet pump, the stratum is explored in the area ofperforation and the stratum fluid coming into the well; then thetransmitter and receiver-transducer of physical fields together with thesealing assembly are lifted out of the well, a valve insert with a checkvalve, which is seated onto the mounting seat in the valve assembly, aswell as a blocking insert with the bypass passage, which is seated ontothe mounting seat in the valve assembly and separates the inner cavityof the piping string and the area around the piping string, are droppedinto the well; thereafter a lightweight fluid or an inert gas issupplied to the area around the piping string through the recirculationvalve, peening it into the inner cavity of the piping string, thuslowering the hydrostatic pressure in the well bottom zone; and the wellis put into flowing operation, and after the well output is reduced dueto the depletion of the stratum energy the well is deadened through therecirculation valve with a higher density fluid thus closing the checkvalve preventing the higher density fluid from entering into the areaunder the packer, the blocking insert is removed, a depression insertwith an autonomous pressure gauge and a flowmeter is dropped into thepiping string and the stratum fluid is pumped out of the well atdifferent pressure drawdown by supplying the liquid working medium tothe active nozzle of the jet pump, simultaneously measuring the welloutput at the surface and under the jet pump, then the depression insertwith the autonomous pressure gauge and the flowmeter is removed out ofthe well, their readings of the bottom-hole pressures and flow rates areobtained, a flow rate vs. bottom-hole pressure data is plotted and byinterpreting the plot the size of the pump required for forced oilproduction is determined; then, with the use of the assembly fordisconnecting and connecting of the piping string, the jet pump with theabove-arranged piping string is disconnected, lifted to the surface, anoil production pump of required capacity is lowered on the piping stringand connected to the piping string part remaining in the well by usingthe assembly for disconnecting and connecting of the piping string, andthe well is put into forced operation.

The stated objective in the part of the unit is achieved owing to thefact that the well jet unit comprises, being installed on the pipingstring, a packer and a jet pump with the active nozzle, the mixingchamber and the through passage with the mounting seat for installationof the sealing assembly with the axial passage, the said jet unitfurther comprises a transmitter and receiver-transducer of physicalfields, which is arranged in the area below the packer on the side ofentry of the pumped-out medium into the jet pump and installed on thewell-logging cable fed through the axial passage of the sealingassembly, the output of the jet pump is connected to the area around thepiping string, the input of the passage in the jet pump for supplyingthe pumped out medium is connected to the inner cavity of the pipingstring below the sealing assembly, and the input of the passage forsupplying the working medium to the active nozzle is connected to theinner cavity of the piping string above the sealing assembly, further,according to the invention, the piping string is provided with a shankwith the input cup, the valve assembly with the mounting seat forinstalling the valve insert with the check valve, the assembly fordisconnecting and connecting the piping string, and the recirculationvalve installed in the wall of the piping string above the jet pump; thepacker is made with the central passage; the sealing assembly isinstalled with the possibility of being replaced by other functionalinserts: a blocking insert, a pressurizing insert, a depression insertand an insert for recording stratum pressure restoration curves with theuse of autonomous well gauges; the receiver-transducer of physicalfields is made with the possibility of being replaced by a perforator oran instrument for acoustic impact on a stratum or strata; the abovebeing taken into account, the diameter D₁₄ of the passage for supplyingthe working medium is not less than the inner diameter D₁₃ of the mixingchamber, the diameter D₆ of the through passage below the mounting seatis at least 0.7 mm less than its diameter D₃ above the mounting seat,the diameter D₄ of the sealing assembly is at least 1.4 mm less than thediameter D₁ of the inner cavity of the piping string, the diameter D₅ ofthe axial passage in the sealing assembly is at least 0.008 mm greaterthan the diameter D₂ of the well-logging cable, the diameter D₁₀ of thetransmitter and receiver-transducer of physical fields is at least 1.4mm less than the diameter D₆ of the through passage below the mountingseat, the diameter D₉ of the central passage in the packer is at least1.4 mm greater than the diameter of the transmitter and transducer ofphysical fields, the diameter D₈ of the through passage in the valveassembly below the mounting seat for the valve insert is at least 0.7 mmless than its diameter D₇ above the mounting seat, the diameter D₁₆ ofthe valve insert with the check valve is at least 1 mm less than thediameter D₆ of the through passage in the jet pump under the mountingseat, the outer diameter D₁₅ of the jet pump is at least 2 mm less thanthe inner diameter D₁₁ of the casing string, the inner diameter D₁₃ ofthe mixing chamber is within 1.2 to 1.4 inner diameters D₁₂ of thenozzle, the distance L₁ between cross-sections of the nozzle and themixing chamber is within 0.4 to 1.4 inner diameters D₁₂ of the nozzle,and the length L₂ of the sealing assembly is not less than its outerdiameter D₄; the blocking insert has a bypass passage with the diameterD₁₇ being at least 20 mm and is provided with the head for the purposeof being removed out of the well, and the transmitter andreceiver-transducer of physical fields are made with the possibility ofbeing operated in the area under the packer both when the jet pump isoperated and when it is shut down.

The functional analysis of the well jet unit has shown that thereliability of its operation may be increased both by optimizing theprocedure of testing and developing wells and by optimizing thearrangement of the jet pump in its body and making various components ofthe unit under strictly defined dimensions.

It has been found that the above procedure enables to exploit the blastenergy most effectively when carrying out works on intensifying oilinflow from the productive stratum, and that the conditions are createdwhich prevent mud particles and other media from settling in the wellafter perforating it, which is achieved due to a pressure drawdown inthe area under the packer. At a given pressure drawdown the jet pumpremoves the said particles and media from the productive stratum, andthe transmitter and receiver-transducer of physical fields is used forwell exploration or for impacting a stratum or strata by physicalfields. At the same time the possibility exists for controlling thepressure drawdown value by controlling the pumping rate of the liquidworking medium. Moreover, when testing strata it is possible to adjustthe pumping-out mode through changing the pressure of the liquid workingmedium supplied to the nozzle of the jet pump. In the course ofexploration it is possible to move the transmitter andreceiver-transducer of physical fields along the well, and explorationmay be conducted both when the jet pump is operated and when it is shutdown. Covering both the passage for supplying the liquid working mediumand the passage for supplying the pumped-out medium with the blockinginsert enables to prevent foreign objects that may clog the jet pumpfrom entering into it, which also enables to improve the reliability ofthe unit. The check valve, which is installed in the piping string belowthe jet pump, enables to prevent the products of stratum perforationfrom entering the well when stopping works in the well, e.g., atequipment changes. Moreover, it enables to measure the well parametersmore accurately which enables to conduct more qualitative processing ofthe well and prepare it for exploitation. The recirculation valveinstalled in the wall of the piping string enables to change the mediumin the piping string and regulate the hydrostatic pressure in the wellbottom zone. Thus, this working method enables high-quality developmentof wells after drilling, their comprehensive exploration and testing invarious modes.

It has been found during the studies that the diameter of the passagefor supplying the liquid working medium may not be chosen arbitrarily.It is due to the fact that an excessively large diameter of the saidpassage results in lowering the durability of the unit while anexcessively low diameter reduces the capacity of the jet pump. It hasbeen found out in this connection that if the diameter of the passagefor supplying the liquid working medium is made not less than the innerdiameter of the mixing chamber and the inner diameter of the mixingchamber is made within 1.2 to 1.4 inner diameters of the nozzle and thedistance between sections of the nozzle and the mixing chamber is madewithin 0.4 to 1.4 inner diameters of the nozzle, then it enables toensure the supply of required quantities of the liquid working medium tothe nozzle of the jet pump and ensure the maximum possibly capacity ofthe jet pump while achieving the necessary strength of the jet pumpbody; it has been also found that if the diameter of the through passagebelow the mounting seat is made at least 0.7 mm less than its diameterabove the mounting seat, then it enables to ensure tight installation ofthe sealing assembly and other inserts, e.g. the blocking insert, at themounting seat, which prevents the medium from flowing along the wall ofthe insert installed on the mounting seat. The upper limit is defined bythe structural features of the mounting seat and the dimensions of thewell. If the diameter of the sealing assembly is made at least 1.4 mmless than the diameter of the inner cavity of the piping string, then itenables to avoid possible sticking of the insert when being lowered andinstalled onto the mounting seat. As has been said, in the process ofoperating the unit it is necessary to move the instruments and equipmentinstalled on the cable along the well and, at the same time, to minimizeflow of the medium through the axial passage of the sealing assembly. Ithas been achieved after making the diameter of the axial passage in thesealing assembly at least 0.008 mm greater than the diameter of thecable on which the instruments and equipment are installed. It has beenfound that if the diameter of the transmitter and receiver-transducer ofphysical fields and the diameter of the perforator are made at least 1.4mm less than the diameter of the through passage below the mounting seatas well as is the diameter of the central passage in the packer is madeat least 1.4 mm greater than the diameter of the transmitter andtransducer of physical fields and the diameter of the perforator and thediameter of the valve insert with the check valve is made at least 1 mmless than the diameter of the through passage of the jet pump under themounting seat, then it enables to avoid sticking of the transmitter andreceiver-transducer of physical fields and the perforator of the valveinsert when installing them and moving along the piping string. If thediameter of the through passage in the valve assembly below the mountingseat for the valve insert is made at least 0.7 mm less than its diameterabove the mounting seat, then it enables to ensure tight installation ofthe valve insert with the check valve on the mounting seat whileavoiding overflow of the medium from the well space above the checkvalve. If the outer diameter of the jet pump is made at least 2 mm lessthan the inner diameter of the casing string, then it enables to passthe maximum quantity, which is based on the pump capacity, of the pumpedout medium through the jet pump with minimum hydraulic losses. As to theupper limit, it is determined by the strength characteristics of the jetpump construction, principally by those of the jet pump body, and thepermissible minimum values of the inner diameter of the piping string.The length of the sealing assembly should not be less than its outerdiameter. It eliminates misalignment when installing the sealingassembly onto the mounting seat and, consequently, prevents the mediumfrom flowing along the wall of the sealing assembly and prevents theassembly from sticking in the process of its installation and removal.The blocking insert should have the bypass passage with the diameter atleast 20 mm and should be provided with the head for removing it out ofthe well. If the bypass passage is made with the diameter less than 20mm, excessive hydraulic resistance occurs, which sharply reduces thework efficiency when testing and developing wells in a number of casesit intensifies the process of clogging the bypass passage, which resultsin work stoppage at the well.

Thus, the above-described totality of interdependent parameters and thesequence of operations ensure the achievement of the inventionobjective—to optimize the method of operation of a well jet unit whentesting and developing wells, the arrangement and the dimensions ofvarious components of the unit, and, thus, to raise the reliability ofoperation of the well jet unit.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a longitudinal section of the unit with the sealing assemblyand the perforator installed thereon.

FIG. 2 is a longitudinal section of the unit with the sealing assembly,the transmitter and receiver-transducer of physical fields installedthereon.

FIG. 3 is a longitudinal section of the unit with the blocking insertinstalled thereon.

FIG. 4 is a longitudinal section of the unit with the installeddepression insert with the autonomous pressure gauge and the flowmeterand the valve insert.

FIG. 5 is a longitudinal section of the unit with the lifted pipingstring with the jet unit.

FIG. 6 is a longitudinal section of the unit with the installed oilproduction pump.

FIG. 7 is the portion A from FIG. 1.

FIG. 8 is a longitudinal section of the sealing assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The well jet unit comprises installed on the piping string 1 the packer2 with the central passage 3 and the jet pump 4 with the active nozzle5, the mixing chamber 6 and the through passage 7 with the mounting seat8 for installation of the sealing assembly 9 with the axial passage 10,the said unit further comprises the transmitter and receiver-transducerof physical fields 11, which is arranged in the area below the packer onthe side of entry of the pumped-out medium into the jet pump 4 andinstalled on the well-logging cable 12 fed through the axial passage 10of the sealing assembly 9. The output of the jet pump 4 is connected tothe area around the piping string 1, the input side of the passage 13 inthe jet pump 4 for supplying the working medium is connected to theinner cavity of the piping string 1 below the sealing assembly 9, andthe input side of the passage 14 for supplying the liquid working mediumto the active nozzle 5 is connected to the inner cavity of the pipingstring 1 above the sealing assembly 9. The unit is made with thepossibility of installing the perforator onto the well-logging cable 12.The piping string 1 is provided with a shank 16 with the input cup 17,the valve assembly 18 with the mounting seat 19 for installing the valveinsert 20 with the check valve 21, the assembly 22 for disconnecting andconnecting the piping string 1, and the recirculation valve 23 installedin the wall of the piping string above the jet pump 4; the sealingassembly 9 is installed with the possibility of being replaced by otherfunctional inserts: the blocking insert 24, the pressurizing insert, thedepression insert 25 and the insert for recording stratum pressurerestoration curves with the use of autonomous well gauges, e.g., thedepression insert 25 is made with the autonomous well gauges 26, namely,the pressure gauge and the flowmeter, the transmitter andreceiver-transducer of physical fields 11 is made with the possibilityof being replaced by the perforator 15 or an instrument for acousticimpact on a stratum or strata; the above being taken into account, thediameter D₁₄ of the passage 14 for supplying the working medium is notless than the inner diameter D₁₃ of the mixing chamber 6, the diameterD₆ of the through passage 7 below the mounting seat 8 is at least 0.7 mmless than its diameter D₃ above the mounting seat 8, the diameter D₄ ofthe sealing assembly 9 is at least 1.4 mm less than the diameter D₁ ofthe inner cavity of the piping string 1, the diameter D₅ of the axialpassage 10 in the sealing assembly 9 is at least 0.008 mm greater thanthe diameter D₂ of the well-logging cable 12, the diameter D₁₀ of thetransmitter and receiver-transducer of physical fields 11 is at least1.4 mm less than the diameter D₆ of the through passage 7 below themounting seat 8, the diameter D₉ of the central passage 3 in the packer2 is at least 1.4 mm greater than the diameter of the transmitter andtransducer of physical fields 11, the diameter D₈ of the through passage27 in the valve assembly 18 below the mounting seat 19 for the valveinsert 20 is at least 0.7 mm less than its diameter D₇ above themounting seat 19, the diameter D₁₆ of the valve insert 20 with the checkvalve 21 is at least 1 mm less than the diameter D₆ of the throughpassage 7 in the jet pump 4 under the mounting seat 8, the outerdiameter D₁₅ of the jet pump 4 is at least 2 mm less than the innerdiameter D₁₁ of the casing string 28, the inner diameter D₁₃ of themixing chamber 6 is within 1.2 to 1.4 inner diameters D₁₂ of the nozzle5, the distance L₁ between cross-sections of the nozzle 5 and the mixingchamber 6 is within 0.4 to 1.4 inner diameters D₁₂ of the nozzle 5, andthe length L₂ of the sealing assembly 9 is not less than its outerdiameter D₄; the blocking insert 24 has a bypass passage 29 with thediameter D₁₇ being at least 20 mm and is provided with the head 32 forthe purpose of being removed out of the well, and the transmitter andreceiver-transducer of physical fields 11 are made with the possibilityof being operated in the area under the packer both when the jet pump 4is operated and when it is shut down.

The method of operation of the well jet unit when testing and developingwells is implemented as follows.

First, the piping string 1 is assembled by successively installing,top-down on the piping string 1, the jet pump 4, the assembly 22 fordisconnecting and connecting of the piping string 1, the valve assembly18 with the mounting seat 19 for installing the check valve 21, thepacker 2 with the central passage 3 and the shank 16 with the input cup17. Then, the whole assembled unit is lowered in the well and the packeris released; when lowering, the packer 2 being installed at least 50meters above the roof of the productive stratum 30, and the input cup 17being installed no more than 2 meters above the roof of that stratum 30.After releasing the packer 2, the perforator 15 on the well-loggingcable 12 is lowered into the well together with the sealing assembly 9installed above it, the sealing assembly 9 being seated onto themounting seat 8 in the through passage 7 of the jet pump 4, theperforator 15 being arranged against the productive stratum 30; then arequired pressure drawdown onto the stratum is created, the perforator15 is blasted, and the stratum is drained, e.g. for a long time, untilthe process fluid under the packer 2 is completely replaced by thestratum fluid by supplying the liquid working medium to the nozzle 5 ofthe jet pump 4 and pumping out the process fluid from the area under thepacker 2 with the jet pump 4, thus creating a pressure drawdown, asnecessary for pumping out the process fluid, in the area under thepacker 2. Then the perforator 15 together with the sealing assembly 9are lifted to the surface, and the transmitter and receiver-transducerof physical fields 11 with the sealing assembly 9 are lowered into thewell on the well-logging cable 12. Explorations of the stratum 30 in thearea of perforation and the stratum fluid coming into the well arecarried out when the jet pump 4 is operated. Then the transmitter andreceiver-transducer of physical fields 11 together with the sealingassembly 9 are lifted out of the well, and the valve insert 20 with thecheck valve 21, which is seated onto the mounting seat 19 in the valveassembly 18, as well as the blocking insert 24 with the bypass passage29, which is seated onto the mounting seat 8 in the through passage 7 ofthe jet pump 4, are dropped into the well. The blocking insert 24separates the inner cavity of the piping string 1 and the area aroundthe piping string 1. By supplying a lightweight fluid or an inert gas tothe area around the piping string 1 through the recirculation valve itis peened into the inner cavity of the piping string 1, thus loweringthe hydrostatic pressure in the well bottom zone, and this enables toput the well into flowing operation. After the well output is reduceddue to the depletion of the energy of the stratum 30, the well isdeadened through the recirculation valve(s) 23 with a higher densityfluid thus closing the check valve 21 preventing the higher densityfluid from entering into the area under the packer and contaminating thestratum 30. Then the blocking insert 24 is removed, the depressioninsert 25 with the autonomous gauges 26 is dropped into the pipingstring 1. In this case the gauges are a pressure gauge and a flowmeter.By supplying the liquid working medium to the active nozzle 5 of the jetpump 4 the stratum fluid is pumped out of the well at different pressuredrawdown, simultaneously the well output at the surface and under thejet pump 4 is measured, after which the depression insert 25 with theautonomous pressure gauge and the flowmeter is removed, their readingsof the bottom-hole pressures and flow rates are obtained, and a flowrate vs. bottom-hole pressure data is plotted. By interpreting theobtained measurements the size of the pump 31 required for forced oilproduction is determined. Then, with the use of the assembly 22 fordisconnecting and connecting of the piping string 1, the jet pump 4 andthe above-arranged piping string 1 are disconnected, lifted to thesurface, and the oil production pump 31 of required capacity is loweredon the piping string 1 and connected to the part, which remained in thewell, of the piping string 1, using the assembly 22 for disconnectingand connecting of the piping string 1, and the well is put into forcedoperation.

INDUSTRIAL APPLICABILITY

This invention may be utilized in the oil industry in testing anddeveloping wells, and in other industries where various media areextracted from wells.

1. The method of operation of the well jet unit in testing anddeveloping wells, which includes installation of a jet pump with athrough passage and a packer onto the piping string, lowering of thatassembly into the well, release of the packer and creation of a requiredpressure drawdown in the area below the packer by pumping the processfluid out of the area below the packer with the jet pump, characterizedin that the piping string is additionally provided with: an assembly fordisconnecting and connecting the piping string, a valve assembly with amounting seat for installation of a check valve, a shank with an inputcup, and a recirculation valve installed in the wall of the pipingstring above the said jet pump; first the piping string is assembled bysuccessively installing, top-down on the piping string, a jet pump, anassembly for disconnecting and connecting of the piping string, a valveassembly with the mounting seat for installing a check valve, a packerand a shank with an input cup; when lowering the assembly the packer isinstalled at least 50 meters above the roof of the productive stratumand the input cup is installed no more than 2 meters above the roof ofthat stratum, after releasing the packer a perforator on a well-loggingcable is lowered into the well together with a sealing assemblyinstalled thereon which is seated onto the mounting seat in the throughpassage of the jet pump, the said perforator being arranged against theproductive stratum, further a required pressure drawdown onto thestratum is created with the use of the jet pump, the perforator isblasted, and the stratum is drained until the process fluid under thepacker is completely replaced by the stratum fluid; then the perforatortogether with the sealing assembly are lifted to the surface, atransmitter and receiver-transducer of physical fields with the sealingassembly are lowered into the well on the well-logging cable, a valveinsert with a check valve, which is seated onto the mounting seat in thethrough passage in the valve assembly, as well as a blocking insert withthe bypass passage, which is seated onto the mounting seat in the valveassembly and separates the inner cavity of the piping string and thearea around the piping string, are dropped into the well; thereafter alightweight fluid or an inert gas is supplied to the area around thepiping string through the recirculation valve, peening it into the innercavity of the piping string, thus lowering the hydrostatic pressure inthe well bottom zone; and the well is put into flowing operation, andafter the well output is reduced due to the depletion of the stratumenergy the well is deadened through the recirculation valve with ahigher density fluid thus closing the check valve preventing the higherdensity fluid from entering into the area under the packer, the blockinginsert is removed, a depression insert with an autonomous pressure gaugeand a flowmeter is dropped into the piping string, and the stratum fluidis pumped out of the well at different pressure drawdown by supplyingthe liquid working medium to the active nozzle of the jet pump,simultaneously measuring the well output at the surface and under thejet pump, then the depression insert with the autonomous pressure gaugeand the flowmeter is removed out of the well, their readings of thebottom-hole pressures and flow rates are obtained, a flow rate vs.bottom-hole pressure data is plotted and by interpreting the plot thesize of the pump required for forced oil production is determined; then,with the use of the assembly for disconnecting and connecting of thepiping string, the jet pump with the above-arranged piping string isdisconnected, lifted to the surface, an oil production pump of requiredcapacity is lowered on the piping string and connected to the pipingstring part remaining in the well by using the assembly fordisconnecting and connecting of the piping string, and the well is putinto forced operation.
 2. The well jet unit, which comprises, beinginstalled on the piping string, a packer and a jet pump with the activenozzle, the mixing chamber and the through passage with the mountingseat for installation of the sealing assembly with the axial passage,the said jet unit further comprises a transmitter andreceiver-transducer of physical fields, which is arranged in the areabelow the packer on the side of entry of the pumped-out medium into thejet pump and installed on the well-logging cable fed through the axialpassage of the sealing assembly, the output of the jet pump is connectedto the area around the piping string, the input of the passage in thejet pump for supplying the pumped out medium is connected to the innercavity of the piping string below the sealing assembly, and the input ofthe passage for supplying the working medium to the active nozzle isconnected to the inner cavity of the piping string above the sealingassembly, characterized in that the piping string is provided with ashank with the input cup, the valve assembly with the mounting seat forinstalling the valve insert with the check valve, the assembly fordisconnecting and connecting the piping string, and the recirculationvalve installed in the wall of the piping string above the jet pump; thepacker is made with the central passage; the sealing assembly isinstalled with the possibility of being replaced by other functionalinserts: a blocking insert, a pressurizing insert, a depression insertand an insert for recording stratum pressure restoration curves with theuse of autonomous well gauges; the receiver-transducer of physicalfields is made with the possibility of being replaced by a perforator oran instrument for acoustic impact on a stratum or strata; the abovebeing taken into account, the diameter D₁₄ of the passage for supplyingthe working medium is not less than the inner diameter D₁₃ of the mixingchamber, the diameter D₆ of the through passage below the mounting seatis at least 0.7 mm less than its diameter D₃ above the mounting seat,the diameter D₄ of the sealing assembly is at least 1.4 mm less than thediameter D₁ of the inner cavity of the piping string, the diameter D₅ ofthe axial passage in the sealing assembly is at least 0.008 mm greaterthan the diameter D₂ of the well-logging cable, the diameter D₁₀ of thetransmitter and receiver-transducer of physical fields is at least 1.4mm less than the diameter D₆ of the through passage below the mountingseat, the diameter D₉ of the central passage in the packer is at least1.4 mm greater than the diameter of the transmitter and transducer ofphysical fields, the diameter D₈ of the through passage in the valveassembly below the mounting seat for the valve insert is at least 0.7 mmless than its diameter D₇ above the mounting seat, the diameter D₁₆ ofthe valve insert with the check valve is at least 1 mm less than thediameter D₆ of the through passage in the jet pump under the mountingseat, the outer diameter D₁₅ of the jet pump is at least 2 mm less thanthe inner diameter D₁₁ of the casing string, the inner diameter D₁₃ ofthe mixing chamber is within 1.2 to 1.4 inner diameters D₁₂ of thenozzle, the distance L₁ between cross-sections of the nozzle and themixing chamber is within 0.4 to 1.4 inner diameters D₁₂ of the nozzle,and the length L₂ of the sealing assembly is not less than its outerdiameter D₄; the blocking insert has a bypass passage with the diameterD₁₇ being at least 20 mm and is provided with the head for the purposeof being removed out of the well, and the transmitter andreceiver-transducer of physical fields are made with the possibility ofbeing operated in the area under the packer both when the jet pump isoperated and when it is shut down.